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; RUN: opt -attributor --attributor-disable=false -S < %s | FileCheck %s
declare void @no_return_call() nofree noreturn nounwind readnone
declare void @normal_call() readnone
declare i32 @foo()
declare i32 @foo_noreturn() noreturn
declare i32 @bar() nosync readnone
; CHECK: Function Attrs: nofree norecurse nounwind uwtable willreturn
define i32 @volatile_load(i32*) norecurse nounwind uwtable {
%2 = load volatile i32, i32* %0, align 4
ret i32 %2
}
; CHECK: Function Attrs: nofree norecurse nosync nounwind uwtable willreturn
; CHECK-NEXT: define internal i32 @internal_load(i32* nonnull %0)
define internal i32 @internal_load(i32*) norecurse nounwind uwtable {
%2 = load i32, i32* %0, align 4
ret i32 %2
}
; TEST 1: Only first block is live.
; CHECK: Function Attrs: nofree nosync nounwind
; CHECK-NEXT: define i32 @first_block_no_return(i32 %a, i32* nonnull %ptr1, i32* %ptr2)
define i32 @first_block_no_return(i32 %a, i32* nonnull %ptr1, i32* %ptr2) #0 {
entry:
call i32 @internal_load(i32* %ptr1)
; CHECK: call i32 @internal_load(i32* nonnull %ptr1)
call void @no_return_call()
; CHECK: call void @no_return_call()
; CHECK-NEXT: unreachable
%cmp = icmp eq i32 %a, 0
br i1 %cmp, label %cond.true, label %cond.false
cond.true: ; preds = %entry
call i32 @internal_load(i32* %ptr2)
; CHECK: call i32 @internal_load(i32* %ptr2)
%load = call i32 @volatile_load(i32* %ptr1)
call void @normal_call()
%call = call i32 @foo()
br label %cond.end
cond.false: ; preds = %entry
call void @normal_call()
%call1 = call i32 @bar()
br label %cond.end
cond.end: ; preds = %cond.false, %cond.true
%cond = phi i32 [ %call, %cond.true ], [ %call1, %cond.false ]
ret i32 %cond
}
; TEST 2: cond.true is dead, but cond.end is not, since cond.false is live
; This is just an example. For example we can put a sync call in a
; dead block and check if it is deduced.
; CHECK: Function Attrs: nosync
; CHECK-NEXT: define i32 @dead_block_present(i32 %a, i32* %ptr1)
define i32 @dead_block_present(i32 %a, i32* %ptr1) #0 {
entry:
%cmp = icmp eq i32 %a, 0
br i1 %cmp, label %cond.true, label %cond.false
cond.true: ; preds = %entry
call void @no_return_call()
; CHECK: call void @no_return_call()
; CHECK-NEXT: unreachable
%call = call i32 @volatile_load(i32* %ptr1)
br label %cond.end
cond.false: ; preds = %entry
call void @normal_call()
%call1 = call i32 @bar()
br label %cond.end
cond.end: ; preds = %cond.false, %cond.true
%cond = phi i32 [ %call, %cond.true ], [ %call1, %cond.false ]
ret i32 %cond
}
; TEST 3: both cond.true and cond.false are dead, therfore cond.end is dead as well.
define i32 @all_dead(i32 %a) #0 {
entry:
%cmp = icmp eq i32 %a, 0
br i1 %cmp, label %cond.true, label %cond.false
cond.true: ; preds = %entry
call void @no_return_call()
; CHECK: call void @no_return_call()
; CHECK-NEXT: unreachable
%call = call i32 @foo()
br label %cond.end
cond.false: ; preds = %entry
call void @no_return_call()
; CHECK: call void @no_return_call()
; CHECK-NEXT: unreachable
%call1 = call i32 @bar()
br label %cond.end
cond.end: ; preds = %cond.false, %cond.true
%cond = phi i32 [ %call, %cond.true ], [ %call1, %cond.false ]
ret i32 %cond
}
declare i32 @__gxx_personality_v0(...)
; TEST 4: All blocks are live.
; CHECK: define i32 @all_live(i32 %a)
define i32 @all_live(i32 %a) #0 {
entry:
%cmp = icmp eq i32 %a, 0
br i1 %cmp, label %cond.true, label %cond.false
cond.true: ; preds = %entry
call void @normal_call()
%call = call i32 @foo_noreturn()
br label %cond.end
cond.false: ; preds = %entry
call void @normal_call()
%call1 = call i32 @bar()
br label %cond.end
cond.end: ; preds = %cond.false, %cond.true
%cond = phi i32 [ %call, %cond.true ], [ %call1, %cond.false ]
ret i32 %cond
}
; TEST 5 noreturn invoke instruction replaced by a call and an unreachable instruction
; put after it.
; CHECK: define i32 @invoke_noreturn(i32 %a)
define i32 @invoke_noreturn(i32 %a) personality i8* bitcast (i32 (...)* @__gxx_personality_v0 to i8*) {
entry:
%cmp = icmp eq i32 %a, 0
br i1 %cmp, label %cond.true, label %cond.false
cond.true: ; preds = %entry
call void @normal_call()
%call = invoke i32 @foo_noreturn() to label %continue
unwind label %cleanup
; CHECK: call i32 @foo_noreturn()
; CHECK-NEXT unreachable
cond.false: ; preds = %entry
call void @normal_call()
%call1 = call i32 @bar()
br label %cond.end
cond.end: ; preds = %cond.false, %continue
%cond = phi i32 [ %call, %continue ], [ %call1, %cond.false ]
ret i32 %cond
continue:
br label %cond.end
cleanup:
%res = landingpad { i8*, i32 }
catch i8* null
ret i32 0
}
; TEST 6: Undefined behvior, taken from LangRef.
; FIXME: Should be able to detect undefined behavior.
; CHECK define @ub(i32)
define void @ub(i32* ) {
%poison = sub nuw i32 0, 1 ; Results in a poison value.
%still_poison = and i32 %poison, 0 ; 0, but also poison.
%poison_yet_again = getelementptr i32, i32* %0, i32 %still_poison
store i32 0, i32* %poison_yet_again ; Undefined behavior due to store to poison.
ret void
}
define void @inf_loop() #0 {
entry:
br label %while.body
while.body: ; preds = %entry, %while.body
br label %while.body
}
; TEST 7: Infinite loop.
; FIXME: Detect infloops, and mark affected blocks dead.
define i32 @test5(i32, i32) #0 {
%3 = icmp sgt i32 %0, %1
br i1 %3, label %cond.if, label %cond.elseif
cond.if: ; preds = %2
%4 = tail call i32 @bar()
br label %cond.end
cond.elseif: ; preds = %2
call void @inf_loop()
%5 = icmp slt i32 %0, %1
br i1 %5, label %cond.end, label %cond.else
cond.else: ; preds = %cond.elseif
%6 = tail call i32 @foo()
br label %cond.end
cond.end: ; preds = %cond.if, %cond.else, %cond.elseif
%7 = phi i32 [ %1, %cond.elseif ], [ 0, %cond.else ], [ 0, %cond.if ]
ret i32 %7
}
define void @rec() #0 {
entry:
call void @rec()
ret void
}
; TEST 8: Recursion
; FIXME: everything after first block should be marked dead
; and unreachable should be put after call to @rec().
define i32 @test6(i32, i32) #0 {
call void @rec()
%3 = icmp sgt i32 %0, %1
br i1 %3, label %cond.if, label %cond.elseif
cond.if: ; preds = %2
%4 = tail call i32 @bar()
br label %cond.end
cond.elseif: ; preds = %2
call void @rec()
%5 = icmp slt i32 %0, %1
br i1 %5, label %cond.end, label %cond.else
cond.else: ; preds = %cond.elseif
%6 = tail call i32 @foo()
br label %cond.end
cond.end: ; preds = %cond.if, %cond.else, %cond.elseif
%7 = phi i32 [ %1, %cond.elseif ], [ 0, %cond.else ], [ 0, %cond.if ]
ret i32 %7
}
; TEST 9: Recursion
; FIXME: contains recursive call to itself in cond.elseif block
define i32 @test7(i32, i32) #0 {
%3 = icmp sgt i32 %0, %1
br i1 %3, label %cond.if, label %cond.elseif
cond.if: ; preds = %2
%4 = tail call i32 @bar()
br label %cond.end
cond.elseif: ; preds = %2
%5 = tail call i32 @test7(i32 %0, i32 %1)
%6 = icmp slt i32 %0, %1
br i1 %6, label %cond.end, label %cond.else
cond.else: ; preds = %cond.elseif
%7 = tail call i32 @foo()
br label %cond.end
cond.end: ; preds = %cond.if, %cond.else, %cond.elseif
%8 = phi i32 [ %1, %cond.elseif ], [ 0, %cond.else ], [ 0, %cond.if ]
ret i32 %8
}
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